1. Field of the Invention
This invention relates generally to exercise machines, and more particularly to a stepping-type exercise machine.
2. Description of Related Art
The following patents represent the state of the art:
Palmer, U.S. Pat. No. 5,665,033, teaches an exercise machine that simulates the movements made during snow skiing to exercise the muscles used during such movements. The exercise machine includes a pair of elongate foot support arms with foot support portions mounted for simultaneous vertical and horizontal movement with the vertical movement having opposite orientations for the same direction of horizontal movement. Thus, as the foot support portions of the foot support arms move in the same horizontal direction to one side or the other, one foot support portion moves vertically upwardly while the other moves vertically downwardly so that such movement generally defines an X pattern. Movement of the foot support arms is preferably coordinated so that the arms move together in a desired manner with resistance to movement of the arms preferably being adjustable by a user of the machine to adjust the strenuousness of the exercise performed. The desired movement of the foot support portions of the foot support arms may be achieved by mounting each foot support arm for limited rotational movement about separate axis of rotation, each axis of rotation extending along the intersection of perpendicular planes. One plane for each axis of rotation is substantially perpendicular to a machine central plane, with the other planes of each axis of rotation intersecting one another. Upper body supports or handles may be provided which, if desired, can provide upper body exercise in addition to support.
Stevens, U.S. Pat. No. 6,626,806, teaches a damping assembly for a stepping-type exercising device. The exercise device includes a shaft with a base member and a rotatable member respectively mounted thereto. The base member has a first annular surface and the rotatable member has a second annular surface which is engaged with the first annular surface with a friction member clamped therebetween. A driving member is connected to the rotatable member and is connected to a power transferring member. An adjustable member is movably mounted to the shaft and a bearing is mounted to the shaft and located between the adjustable member and the rotatable member. The friction between the rotatable member and the base member can be adjustable by moving the adjustable member to compress the rotatable member toward the base member. See also Steves, U.S. Pat. No. D456,052 (sic).
These patents are hereby incorporated by reference in full.